From waste to resource: utilizing municipal solid waste incineration bottom ash and recycled rubber in pervious concrete pavement

This research investigates the feasibility of using bottom ash from municipal solid waste incinerators (BA) as a replacement for traditional aggregates in pervious concrete (PC). The method employed in these mixes optimizes the use of silica fume as a partial substitute for high-strength Portland cement (Type 52.5), to promote sustainability and reduce waste in construction. Five different replacement percentages, namely, 0% (control), 25%, 50%, 75%, and 100% by volume of natural coarse aggregates, were investigated. Additionally, the impact of incorporating recycled rubber (R) aggregates in varying ratios (5%, 10%, 15%, 20%, 25%, and 30%) with BA aggregates at 100% replacement level was examined. Key properties of PC, including permeability indices (water permeability and connected porosity) and strength indices (compressive, flexural strength, and abrasion resistance), were evaluated. The results showed that increasing BA utilization in PC led to a reduction in both permeability and strength indices compared to the control mix. However, all mixes met the standard requirements for PC, except the 100% BA replacement, which failed to meet the flexural strength requirements. Further investigation demonstrated that different replacements of BA with recycled rubber had an inconsistent effect on the properties of PC. Notably, an optimum replacement value of 15% of recycled rubber resulted in increased compressive and flexural strengths, along with improved resistance to abrasion.